First-order effects

• Facebook instantly becomes one of San Francisco's largest tech tenants, with a single landlord relationship covering an entire 43-story building rather than scattered floors.
• The Transbay subdistrict gains an anchor tenant whose Instagram teams are already working within walking distance, concentrating Facebook's city presence in one corridor.

Second-order effects

• A single tenant absorbing a full tower tightens the supply of large contiguous blocks in San Francisco, pushing rivals and growing mid-size firms to compete for whatever remains or look across the bay — the dynamic behind Square later leasing all of Uber's former Uptown Station space in Oakland (Square's Oakland lease).
• Landlords holding older or less central stock can price against the Transbay benchmark, since a top-tier tenant has now validated whole-building demand at the top of the market.

Third-order effects

• If the pattern holds, big-tech expansion shifts from incremental floor leases to whole-building commitments, concentrating landlord risk in single-tenant towers whose value tracks one company's hiring plans — a exposure that matters if San Francisco's tech-sector job cuts deepen.
• Secondary markets like Oakland become structurally linked to San Francisco pricing: overflow demand from companies priced out of the core, rather than local dynamics, sets their office rents.